Depends if you want to swap the electronics or not.How easy is it to take out a 4.6 GEMS for a 4.6 THOR?
Best to swap the engine and keep the GEMS stuff. I don't know, but I suspect GEMS or Thor might just be an option setting as is the choice between diesel of petrol.Well we know it'll fit! Like @Datatek suggests, you'd be wise to take ALL the electronics too.
The loom will certainly be different, the ECU is mounted in a different place in the engine bay etc etc. The one thing I'd want to double-triple check is where the engine ECU might interface with the BECM. If you need to change the BECM too, surely it isn't worth it!
I think we all agree physical spanner work its simple it fits.
Now the sparky bits
As above you will need the engine ECU and loom and god knows what else LR chucked in to trip peeps up.
As for if you need the BECM, I would say, from all my looking and reading, (so some could be a dream ) the immobilizer for the Gems V Thor are different the Thor is more like the diesel the Gems is different. (prepared to be corrected in my memory)
So as this signal for both comes from the BECM and the diesel and petrol (Gems) are different, well you can see how it gets difficult.
But I would also ask why the need to change?
J
Both my P38 are 1998 reg, but probably 97 manufacture. To be sure, we either need someone with older P38 & Nanocom to connect & see ? . . . . . or the OP to do the swap & document the fun !!You are correct on the BECM. While I can see a Thor era BECM might be backwards compatible and have options for EDC and GEMS, I would doubt a GEMS BECM would have an option for an engine type that hadn't been invented at the time of manufacture. Maybe near the crossover year but I doubt it.
HEVAC is different in the Thor wiring too.
40 years as long as no major changes made ie chassis. See dvla website for full listHow old does it have to be to not need an MOT?